#include "InstCombineInternal.h"
#include "llvm/Analysis/CmpInstAnalysis.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/PatternMatch.h"

Include dependency graph for InstCombineAndOrXor.cpp:

Macros
#define	DEBUG_TYPE "instcombine"

Enumerations
enum	MaskedICmpType { AMask_AllOnes = 1, AMask_NotAllOnes = 2, BMask_AllOnes = 4, BMask_NotAllOnes = 8, Mask_AllZeros = 16, Mask_NotAllZeros = 32, AMask_Mixed = 64, AMask_NotMixed = 128, BMask_Mixed = 256, BMask_NotMixed = 512 }
	Classify (icmp eq (A & B), C) and (icmp ne (A & B), C) as matching patterns that can be simplified. More...

Functions
static unsigned	getFCmpCode (FCmpInst::Predicate CC)
	Similar to getICmpCode but for FCmpInst. More...

static Value *	getNewICmpValue (unsigned Code, bool Sign, Value LHS, Value RHS, InstCombiner::BuilderTy &Builder)
	This is the complement of getICmpCode, which turns an opcode and two operands into either a constant true or false, or a brand new ICmp instruction. More...

static Value *	getFCmpValue (unsigned Code, Value LHS, Value RHS, InstCombiner::BuilderTy &Builder)
	This is the complement of getFCmpCode, which turns an opcode and two operands into either a FCmp instruction, or a true/false constant. More...

static Value *	SimplifyBSwap (BinaryOperator &I, InstCombiner::BuilderTy &Builder)
	Transform BITWISE_OP(BSWAP(A),BSWAP(B)) or BITWISE_OP(BSWAP(A), Constant) to BSWAP(BITWISE_OP(A, B)) More...

static unsigned	getMaskedICmpType (Value A, Value B, Value *C, ICmpInst::Predicate Pred)
	Return the set of patterns (from MaskedICmpType) that (icmp SCC (A & B), C) satisfies. More...

static unsigned	conjugateICmpMask (unsigned Mask)
	Convert an analysis of a masked ICmp into its equivalent if all boolean operations had the opposite sense. More...

static bool	decomposeBitTestICmp (Value LHS, Value RHS, CmpInst::Predicate &Pred, Value &X, Value &Y, Value *&Z)

static Optional< std::pair< unsigned, unsigned > >	getMaskedTypeForICmpPair (Value &A, Value &B, Value &C, Value &D, Value &E, ICmpInst LHS, ICmpInst *RHS, ICmpInst::Predicate &PredL, ICmpInst::Predicate &PredR)
	Handle (icmp(A & B) ==/!= C) &/\| (icmp(A & D) ==/!= E). More...

static Value *	foldLogOpOfMaskedICmps_NotAllZeros_BMask_Mixed (ICmpInst LHS, ICmpInst RHS, bool IsAnd, Value A, Value B, Value C, Value D, Value *E, ICmpInst::Predicate PredL, ICmpInst::Predicate PredR, llvm::InstCombiner::BuilderTy &Builder)
	Try to fold (icmp(A & B) ==/!= C) &/\| (icmp(A & D) ==/!= E) into a single (icmp(A & X) ==/!= Y), where the left-hand side is of type Mask_NotAllZeros and the right hand side is of type BMask_Mixed. More...

static Value *	foldLogOpOfMaskedICmpsAsymmetric (ICmpInst LHS, ICmpInst RHS, bool IsAnd, Value A, Value B, Value C, Value D, Value *E, ICmpInst::Predicate PredL, ICmpInst::Predicate PredR, unsigned LHSMask, unsigned RHSMask, llvm::InstCombiner::BuilderTy &Builder)
	Try to fold (icmp(A & B) ==/!= 0) &/\| (icmp(A & D) ==/!= E) into a single (icmp(A & X) ==/!= Y), where the left-hand side and the right hand side aren't of the common mask pattern type. More...

static Value *	foldLogOpOfMaskedICmps (ICmpInst LHS, ICmpInst RHS, bool IsAnd, llvm::InstCombiner::BuilderTy &Builder)
	Try to fold (icmp(A & B) ==/!= C) &/\| (icmp(A & D) ==/!= E) into a single (icmp(A & X) ==/!= Y). More...

static Value *	foldAndOrOfEqualityCmpsWithConstants (ICmpInst LHS, ICmpInst RHS, bool JoinedByAnd, InstCombiner::BuilderTy &Builder)

static Value *	foldSignedTruncationCheck (ICmpInst ICmp0, ICmpInst ICmp1, Instruction &CxtI, InstCombiner::BuilderTy &Builder)
	General pattern: X & Y. More...

static Instruction *	matchDeMorgansLaws (BinaryOperator &I, InstCombiner::BuilderTy &Builder)
	Match De Morgan's Laws: (~A & ~B) == (~(A \| B)) (~A \| ~B) == (~(A & B)) More...

static Instruction *	foldLogicCastConstant (BinaryOperator &Logic, CastInst *Cast, InstCombiner::BuilderTy &Builder)
	Fold {and,or,xor} (cast X), C. More...

static Instruction *	foldAndToXor (BinaryOperator &I, InstCombiner::BuilderTy &Builder)

static Instruction *	foldOrToXor (BinaryOperator &I, InstCombiner::BuilderTy &Builder)

static bool	canNarrowShiftAmt (Constant *C, unsigned BitWidth)
	Return true if a constant shift amount is always less than the specified bit-width. More...

static Instruction *	matchRotate (Instruction &Or)
	Transform UB-safe variants of bitwise rotate to the funnel shift intrinsic. More...

static bool	areInverseVectorBitmasks (Constant C1, Constant C2)
	If all elements of two constant vectors are 0/-1 and inverses, return true. More...

static Instruction *	foldXorToXor (BinaryOperator &I, InstCombiner::BuilderTy &Builder)
	A ^ B can be specified using other logic ops in a variety of patterns. More...

static Instruction *	visitMaskedMerge (BinaryOperator &I, InstCombiner::BuilderTy &Builder)
	If we have a masked merge, in the canonical form of: (assuming that A only has one use.) \| A \| \|B\| ((x ^ y) & M) ^ y \| D \|. More...

static Instruction *	sinkNotIntoXor (BinaryOperator &I, InstCombiner::BuilderTy &Builder)

Macro Definition Documentation

◆ DEBUG_TYPE

#define DEBUG_TYPE "instcombine"

Definition at line 24 of file InstCombineAndOrXor.cpp.

Enumeration Type Documentation

◆ MaskedICmpType

enum MaskedICmpType

Classify (icmp eq (A & B), C) and (icmp ne (A & B), C) as matching patterns that can be simplified.

One of A and B is considered the mask. The other is the value. This is described as the "AMask" or "BMask" part of the enum. If the enum contains only "Mask", then both A and B can be considered masks. If A is the mask, then it was proven that (A & C) == C. This is trivial if C == A or C == 0. If both A and C are constants, this proof is also easy. For the following explanations, we assume that A is the mask.

"AllOnes" declares that the comparison is true only if (A & B) == A or all bits of A are set in B. Example: (icmp eq (A & 3), 3) -> AMask_AllOnes

"AllZeros" declares that the comparison is true only if (A & B) == 0 or all bits of A are cleared in B. Example: (icmp eq (A & 3), 0) -> Mask_AllZeroes

"Mixed" declares that (A & B) == C and C might or might not contain any number of one bits and zero bits. Example: (icmp eq (A & 3), 1) -> AMask_Mixed

"Not" means that in above descriptions "==" should be replaced by "!=". Example: (icmp ne (A & 3), 3) -> AMask_NotAllOnes

If the mask A contains a single bit, then the following is equivalent: (icmp eq (A & B), A) equals (icmp ne (A & B), 0) (icmp ne (A & B), A) equals (icmp eq (A & B), 0)

Enumerator
AMask_AllOnes
AMask_NotAllOnes
BMask_AllOnes
BMask_NotAllOnes
Mask_AllZeros
Mask_NotAllZeros
AMask_Mixed
AMask_NotMixed
BMask_Mixed
BMask_NotMixed

Definition at line 218 of file InstCombineAndOrXor.cpp.

Function Documentation

◆ areInverseVectorBitmasks()

static bool areInverseVectorBitmasks	(	Constant *	C1,
		Constant *	C2
	)

static

If all elements of two constant vectors are 0/-1 and inverses, return true.

Definition at line 1865 of file InstCombineAndOrXor.cpp.

◆ canNarrowShiftAmt()

static bool canNarrowShiftAmt	(	Constant *	C,
		unsigned	BitWidth
	)

static

Return true if a constant shift amount is always less than the specified bit-width.

If not, the shift could create poison in the narrower type.

Definition at line 1462 of file InstCombineAndOrXor.cpp.

◆ conjugateICmpMask()

static unsigned conjugateICmpMask ( unsigned Mask )

static

Convert an analysis of a masked ICmp into its equivalent if all boolean operations had the opposite sense.

Since each "NotXXX" flag (recording !=) is adjacent to the corresponding normal flag (recording ==), this just involves swapping those bits over.

Definition at line 282 of file InstCombineAndOrXor.cpp.

References AMask_AllOnes, AMask_Mixed, AMask_NotAllOnes, AMask_NotMixed, BMask_AllOnes, BMask_Mixed, BMask_NotAllOnes, BMask_NotMixed, Mask_AllZeros, and Mask_NotAllZeros.

Referenced by foldLogOpOfMaskedICmps(), and foldLogOpOfMaskedICmpsAsymmetric().

◆ decomposeBitTestICmp()

static bool decomposeBitTestICmp	(	Value *	LHS,
		Value *	RHS,
		CmpInst::Predicate &	Pred,
		Value *&	X,
		Value *&	Y,
		Value *&	Z
	)

static

Definition at line 296 of file InstCombineAndOrXor.cpp.

References llvm::decomposeBitTestICmp(), llvm::ConstantInt::get(), llvm::Value::getType(), and llvm::BitmaskEnumDetail::Mask().

◆ foldAndOrOfEqualityCmpsWithConstants()

static Value* foldAndOrOfEqualityCmpsWithConstants	(	ICmpInst *	LHS,
		ICmpInst *	RHS,
		bool	JoinedByAnd,
		InstCombiner::BuilderTy &	Builder
	)

static

Definition at line 807 of file InstCombineAndOrXor.cpp.

References llvm::MCID::Add, B, C, llvm::IRBuilder< T, Inserter >::CreateAdd(), llvm::IRBuilder< T, Inserter >::CreateICmp(), llvm::IRBuilder< T, Inserter >::CreateOr(), D, llvm::dyn_cast(), llvm::ConstantInt::get(), llvm::User::getOperand(), llvm::CmpInst::getPredicate(), llvm::Value::getType(), llvm::CmpInst::ICMP_EQ, llvm::CmpInst::ICMP_NE, llvm::CmpInst::ICMP_UGT, llvm::CmpInst::ICMP_ULE, llvm::isKnownToBeAPowerOfTwo(), llvm::APInt::isNullValue(), llvm::APInt::isPowerOf2(), llvm::ConstantInt::isZero(), llvm::PatternMatch::m_And(), llvm::PatternMatch::m_APInt(), llvm::PatternMatch::m_Value(), llvm::BitmaskEnumDetail::Mask(), llvm::PatternMatch::match(), std::swap(), llvm::APInt::ugt(), and X.

Referenced by areInverseVectorBitmasks(), and foldSignedTruncationCheck().

◆ foldAndToXor()

static Instruction* foldAndToXor	(	BinaryOperator &	I,
		InstCombiner::BuilderTy &	Builder
	)

static

Definition at line 1408 of file InstCombineAndOrXor.cpp.

References assert(), B, llvm::BinaryOperator::CreateNot(), llvm::IRBuilder< T, Inserter >::CreateXor(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::Value::hasOneUse(), llvm::PatternMatch::m_BinOp(), llvm::PatternMatch::m_c_And(), llvm::PatternMatch::m_c_Or(), llvm::PatternMatch::m_Deferred(), llvm::PatternMatch::m_Not(), llvm::PatternMatch::m_Or(), llvm::PatternMatch::m_Value(), and llvm::PatternMatch::match().

Referenced by llvm::InstCombiner::visitAnd().

◆ foldLogicCastConstant()

static Instruction* foldLogicCastConstant	(	BinaryOperator &	Logic,
		CastInst *	Cast,
		InstCombiner::BuilderTy &	Builder
	)

static

◆ foldLogOpOfMaskedICmps()

static Value* foldLogOpOfMaskedICmps	(	ICmpInst *	LHS,
		ICmpInst *	RHS,
		bool	IsAnd,
		llvm::InstCombiner::BuilderTy &	Builder
	)

static

Try to fold (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E) into a single (icmp(A & X) ==/!= Y).

Definition at line 609 of file InstCombineAndOrXor.cpp.

References AMask_AllOnes, AMask_NotAllOnes, assert(), B, BMask_AllOnes, BMask_Mixed, BMask_NotAllOnes, C, conjugateICmpMask(), llvm::IRBuilder< T, Inserter >::CreateAnd(), llvm::IRBuilder< T, Inserter >::CreateICmp(), llvm::IRBuilder< T, Inserter >::CreateOr(), D, llvm::dyn_cast(), E, foldLogOpOfMaskedICmpsAsymmetric(), llvm::ConstantInt::get(), getMaskedTypeForICmpPair(), llvm::Constant::getNullValue(), llvm::ConstantExpr::getOr(), llvm::CmpInst::getPredicate(), llvm::Value::getType(), llvm::ConstantInt::getValue(), llvm::ConstantExpr::getXor(), llvm::CmpInst::ICMP_EQ, llvm::CmpInst::ICMP_NE, llvm::ICmpInst::isEquality(), llvm::BitmaskEnumDetail::Mask(), Mask_AllZeros, and Mask_NotAllZeros.

Referenced by areInverseVectorBitmasks(), and foldSignedTruncationCheck().

◆ foldLogOpOfMaskedICmps_NotAllZeros_BMask_Mixed()

static Value* foldLogOpOfMaskedICmps_NotAllZeros_BMask_Mixed	(	ICmpInst *	LHS,
		ICmpInst *	RHS,
		bool	IsAnd,
		Value *	A,
		Value *	B,
		Value *	C,
		Value *	D,
		Value *	E,
		ICmpInst::Predicate	PredL,
		ICmpInst::Predicate	PredR,
		llvm::InstCombiner::BuilderTy &	Builder
	)

static

Try to fold (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E) into a single (icmp(A & X) ==/!= Y), where the left-hand side is of type Mask_NotAllZeros and the right hand side is of type BMask_Mixed.

For example, (icmp (A & 12) != 0) & (icmp (A & 15) == 8) -> (icmp (A & 15) == 8).

Definition at line 444 of file InstCombineAndOrXor.cpp.

References assert(), B, C, llvm::IRBuilder< T, Inserter >::CreateAnd(), llvm::IRBuilder< T, Inserter >::CreateICmp(), D, llvm::dyn_cast(), E, llvm::ConstantInt::get(), llvm::ConstantInt::getType(), llvm::Value::getType(), llvm::ConstantInt::getValue(), llvm::ConstantExpr::getXor(), llvm::CmpInst::ICMP_EQ, llvm::CmpInst::ICMP_NE, and llvm::ConstantInt::isZero().

Referenced by foldLogOpOfMaskedICmpsAsymmetric().

◆ foldLogOpOfMaskedICmpsAsymmetric()

static Value* foldLogOpOfMaskedICmpsAsymmetric	(	ICmpInst *	LHS,
		ICmpInst *	RHS,
		bool	IsAnd,
		Value *	A,
		Value *	B,
		Value *	C,
		Value *	D,
		Value *	E,
		ICmpInst::Predicate	PredL,
		ICmpInst::Predicate	PredR,
		unsigned	LHSMask,
		unsigned	RHSMask,
		llvm::InstCombiner::BuilderTy &	Builder
	)

static

Try to fold (icmp(A & B) ==/!= 0) &/| (icmp(A & D) ==/!= E) into a single (icmp(A & X) ==/!= Y), where the left-hand side and the right hand side aren't of the common mask pattern type.

Definition at line 574 of file InstCombineAndOrXor.cpp.

References assert(), BMask_Mixed, conjugateICmpMask(), foldLogOpOfMaskedICmps_NotAllZeros_BMask_Mixed(), llvm::ICmpInst::isEquality(), and Mask_NotAllZeros.

Referenced by foldLogOpOfMaskedICmps().

◆ foldOrToXor()

static Instruction* foldOrToXor	(	BinaryOperator &	I,
		InstCombiner::BuilderTy &	Builder
	)

static

Definition at line 1434 of file InstCombineAndOrXor.cpp.

References assert(), B, llvm::BinaryOperator::CreateNot(), llvm::IRBuilder< T, Inserter >::CreateXor(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::Value::hasOneUse(), llvm::PatternMatch::m_And(), llvm::PatternMatch::m_c_And(), llvm::PatternMatch::m_c_Or(), llvm::PatternMatch::m_Not(), llvm::PatternMatch::m_Specific(), llvm::PatternMatch::m_Value(), and llvm::PatternMatch::match().

Referenced by llvm::InstCombiner::visitOr().

◆ foldSignedTruncationCheck()

static Value* foldSignedTruncationCheck	(	ICmpInst *	ICmp0,
		ICmpInst *	ICmp1,
		Instruction &	CxtI,
		InstCombiner::BuilderTy &	Builder
	)

static

General pattern: X & Y.

Where Y is checking that all the high bits (covered by a mask 4294967168) are uniform, i.e. arg & 4294967168 can be either 4294967168 or 0 Pattern can be one of: t = add i32 arg, 128 r = icmp ult i32 t, 256 Or t0 = shl i32 arg, 24 t1 = ashr i32 t0, 24 r = icmp eq i32 t1, arg Or t0 = trunc i32 arg to i8 t1 = sext i8 t0 to i32 r = icmp eq i32 t1, arg This pattern is a signed truncation check.

And X is checking that some bit in that same mask is zero. I.e. can be one of: r = icmp sgt i32 arg, -1 Or t = and i32 arg, 2147483648 r = icmp eq i32 t, 0

Since we are checking that all the bits in that mask are the same, and a particular bit is zero, what we are really checking is that all the masked bits are zero. So this should be transformed to: r = icmp ult i32 arg, 128

Definition at line 931 of file InstCombineAndOrXor.cpp.

◆ foldXorToXor()

static Instruction* foldXorToXor	(	BinaryOperator &	I,
		InstCombiner::BuilderTy &	Builder
	)

static

A ^ B can be specified using other logic ops in a variety of patterns.

We can fold these early and efficiently by morphing an existing instruction.

Definition at line 2458 of file InstCombineAndOrXor.cpp.

Referenced by llvm::InstCombiner::visitXor().

◆ getFCmpCode()

static unsigned getFCmpCode ( FCmpInst::Predicate CC )

static

Similar to getICmpCode but for FCmpInst.

This encodes a fcmp predicate into a four bit mask.

Definition at line 28 of file InstCombineAndOrXor.cpp.

References assert(), llvm::CmpInst::FCMP_FALSE, llvm::CmpInst::FCMP_OEQ, llvm::CmpInst::FCMP_OGE, llvm::CmpInst::FCMP_OGT, llvm::CmpInst::FCMP_OLE, llvm::CmpInst::FCMP_OLT, llvm::CmpInst::FCMP_ONE, llvm::CmpInst::FCMP_ORD, llvm::CmpInst::FCMP_TRUE, llvm::CmpInst::FCMP_UEQ, llvm::CmpInst::FCMP_UGE, llvm::CmpInst::FCMP_UGT, llvm::CmpInst::FCMP_ULE, llvm::CmpInst::FCMP_ULT, llvm::CmpInst::FCMP_UNE, and llvm::CmpInst::FCMP_UNO.

Referenced by foldSignedTruncationCheck().

◆ getFCmpValue()

static Value* getFCmpValue	(	unsigned	Code,
		Value *	LHS,
		Value *	RHS,
		InstCombiner::BuilderTy &	Builder
	)

static

This is the complement of getFCmpCode, which turns an opcode and two operands into either a FCmp instruction, or a true/false constant.

Definition at line 66 of file InstCombineAndOrXor.cpp.

References assert(), llvm::IRBuilder< T, Inserter >::CreateFCmp(), llvm::CmpInst::FCMP_FALSE, llvm::CmpInst::FCMP_TRUE, llvm::ConstantInt::get(), llvm::Value::getType(), and llvm::CmpInst::makeCmpResultType().

Referenced by foldSignedTruncationCheck().

◆ getMaskedICmpType()

static unsigned getMaskedICmpType	(	Value *	A,
		Value *	B,
		Value *	C,
		ICmpInst::Predicate	Pred
	)

static

Return the set of patterns (from MaskedICmpType) that (icmp SCC (A & B), C) satisfies.

Definition at line 233 of file InstCombineAndOrXor.cpp.

References AMask_AllOnes, AMask_Mixed, AMask_NotAllOnes, AMask_NotMixed, B, BMask_AllOnes, BMask_Mixed, BMask_NotAllOnes, BMask_NotMixed, C, llvm::dyn_cast(), llvm::ConstantExpr::getAnd(), llvm::ConstantInt::getValue(), llvm::CmpInst::ICMP_EQ, llvm::APInt::isPowerOf2(), llvm::ConstantInt::isZero(), Mask_AllZeros, and Mask_NotAllZeros.

Referenced by getMaskedTypeForICmpPair().

◆ getMaskedTypeForICmpPair()

static Optional<std::pair<unsigned, unsigned> > getMaskedTypeForICmpPair	(	Value *&	A,
		Value *&	B,
		Value *&	C,
		Value *&	D,
		Value *&	E,
		ICmpInst *	LHS,
		ICmpInst *	RHS,
		ICmpInst::Predicate &	PredL,
		ICmpInst::Predicate &	PredR
	)

static

Handle (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E).

Return the pattern classes (from MaskedICmpType) for the left hand side and the right hand side as a pair. LHS and RHS are the left hand side and the right hand side ICmps and PredL and PredR are their predicates, respectively.

Definition at line 314 of file InstCombineAndOrXor.cpp.

References llvm::decomposeBitTestICmp(), llvm::Constant::getAllOnesValue(), getMaskedICmpType(), llvm::User::getOperand(), llvm::Value::getType(), llvm::ICmpInst::isEquality(), llvm::Type::isIntegerTy(), llvm::PatternMatch::m_And(), llvm::PatternMatch::m_Value(), llvm::PatternMatch::match(), llvm::None, and R2.

Referenced by foldLogOpOfMaskedICmps().

◆ getNewICmpValue()

static Value* getNewICmpValue	(	unsigned	Code,
		bool	Sign,
		Value *	LHS,
		Value *	RHS,
		InstCombiner::BuilderTy &	Builder
	)

static

This is the complement of getICmpCode, which turns an opcode and two operands into either a constant true or false, or a brand new ICmp instruction.

The sign is passed in to determine which kind of predicate to use in the new icmp instruction.

Definition at line 56 of file InstCombineAndOrXor.cpp.

References llvm::IRBuilder< T, Inserter >::CreateICmp(), llvm::getPredForICmpCode(), and llvm::Value::getType().

Referenced by areInverseVectorBitmasks(), foldSignedTruncationCheck(), and foldXorToXor().

◆ matchDeMorgansLaws()

static Instruction* matchDeMorgansLaws	(	BinaryOperator &	I,
		InstCombiner::BuilderTy &	Builder
	)

static

Match De Morgan's Laws: (~A & ~B) == (~(A | B)) (~A | ~B) == (~(A & B))

Definition at line 1265 of file InstCombineAndOrXor.cpp.

References assert(), B, llvm::IRBuilder< T, Inserter >::CreateBinOp(), llvm::BinaryOperator::CreateNot(), llvm::CastInst::getDestTy(), llvm::Value::getName(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::CastInst::getSrcTy(), llvm::Value::hasOneUse(), llvm::IsFreeToInvert(), llvm::PatternMatch::m_Not(), llvm::PatternMatch::m_OneUse(), llvm::PatternMatch::m_Value(), and llvm::PatternMatch::match().

Referenced by llvm::InstCombiner::visitAnd(), and llvm::InstCombiner::visitOr().

◆ matchRotate()

static Instruction* matchRotate ( Instruction & Or )

static

Transform UB-safe variants of bitwise rotate to the funnel shift intrinsic.

Definition at line 1814 of file InstCombineAndOrXor.cpp.

Referenced by foldGuardedRotateToFunnelShift(), and llvm::InstCombiner::visitOr().

◆ SimplifyBSwap()

static Value* SimplifyBSwap	(	BinaryOperator &	I,
		InstCombiner::BuilderTy &	Builder
	)

static

Transform BITWISE_OP(BSWAP(A),BSWAP(B)) or BITWISE_OP(BSWAP(A), Constant) to BSWAP(BITWISE_OP(A, B))

Parameters

I	Binary operator to transform.

Returns: Pointer to node that must replace the original binary operator, or null pointer if no transformation was made.

Definition at line 83 of file InstCombineAndOrXor.cpp.

References llvm::MCID::Add, assert(), llvm::Intrinsic::bswap, llvm::APInt::byteSwap(), C, llvm::IRBuilder< T, Inserter >::CreateBinOp(), llvm::IRBuilder< T, Inserter >::CreateCall(), F(), llvm::ConstantInt::get(), llvm::Intrinsic::getDeclaration(), llvm::ConstantInt::getFalse(), llvm::Instruction::getModule(), llvm::Value::getName(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::ICmpInst::getSignedPredicate(), llvm::ConstantInt::getTrue(), llvm::Value::getType(), llvm::ConstantInt::getValue(), llvm::Value::hasOneUse(), llvm::MipsISD::Hi, llvm::CmpInst::ICMP_UGE, llvm::CmpInst::ICMP_ULT, llvm::Instruction::isBitwiseLogicOp(), llvm::APInt::isMinSignedValue(), llvm::APInt::isMinValue(), llvm::APInt::isPowerOf2(), llvm::MipsISD::Lo, llvm::PatternMatch::m_APInt(), llvm::PatternMatch::m_BSwap(), llvm::PatternMatch::m_Value(), llvm::PatternMatch::match(), llvm::User::setOperand(), llvm::APInt::sle(), llvm::Value::takeName(), llvm::APInt::ule(), and X.

Referenced by llvm::InstCombiner::visitAnd(), llvm::InstCombiner::visitOr(), and llvm::InstCombiner::visitXor().

◆ sinkNotIntoXor()

static Instruction* sinkNotIntoXor	(	BinaryOperator &	I,
		InstCombiner::BuilderTy &	Builder
	)

static

Definition at line 2639 of file InstCombineAndOrXor.cpp.

References llvm::IRBuilder< T, Inserter >::CreateNot(), llvm::Value::getName(), llvm::Value::hasOneUse(), llvm::IsFreeToInvert(), llvm::PatternMatch::m_Not(), llvm::PatternMatch::m_OneUse(), llvm::PatternMatch::m_Value(), llvm::PatternMatch::m_Xor(), llvm::PatternMatch::match(), std::swap(), X, and Y.

Referenced by llvm::InstCombiner::visitXor().

◆ visitMaskedMerge()

static Instruction* visitMaskedMerge	(	BinaryOperator &	I,
		InstCombiner::BuilderTy &	Builder
	)

static

If we have a masked merge, in the canonical form of: (assuming that A only has one use.) | A | |B| ((x ^ y) & M) ^ y | D |.

If M is inverted: | D | ((x ^ y) & ~M) ^ y We can canonicalize by swapping the final xor operand to eliminate the 'not' of the mask. ((x ^ y) & M) ^ x
If M is a constant, and D has one use, we transform to 'and' / 'or' ops because that shortens the dependency chain and improves analysis: (x & M) | (y & ~M)

Definition at line 2603 of file InstCombineAndOrXor.cpp.

References B, C, llvm::IRBuilder< T, Inserter >::CreateAnd(), llvm::IRBuilder< T, Inserter >::CreateNot(), D, llvm::Value::hasOneUse(), llvm::PatternMatch::m_c_And(), llvm::PatternMatch::m_c_Xor(), llvm::PatternMatch::m_CombineAnd(), llvm::PatternMatch::m_Constant(), llvm::PatternMatch::m_Deferred(), llvm::PatternMatch::m_Not(), llvm::PatternMatch::m_OneUse(), llvm::PatternMatch::m_Value(), llvm::PatternMatch::match(), and X.

Referenced by llvm::InstCombiner::visitXor().

Macros

Enumerations

Functions

Macro Definition Documentation

◆ DEBUG_TYPE

Enumeration Type Documentation

◆ MaskedICmpType

Function Documentation

◆ areInverseVectorBitmasks()

◆ canNarrowShiftAmt()

◆ conjugateICmpMask()

◆ decomposeBitTestICmp()

◆ foldAndOrOfEqualityCmpsWithConstants()

◆ foldAndToXor()

◆ foldLogicCastConstant()

◆ foldLogOpOfMaskedICmps()

◆ foldLogOpOfMaskedICmps_NotAllZeros_BMask_Mixed()

◆ foldLogOpOfMaskedICmpsAsymmetric()

◆ foldOrToXor()

◆ foldSignedTruncationCheck()

◆ foldXorToXor()

◆ getFCmpCode()

◆ getFCmpValue()

◆ getMaskedICmpType()

◆ getMaskedTypeForICmpPair()

◆ getNewICmpValue()

◆ matchDeMorgansLaws()

◆ matchRotate()

◆ SimplifyBSwap()

◆ sinkNotIntoXor()

◆ visitMaskedMerge()